Remove Snyk footprint and keep Dependabot as the sole dependency update mechanism

[Copilot]

This issue asked to remove Snyk in favor of Dependabot. The repository already matched that target state, so the PR scope is a no-op code/config update with explicit verification of security automation ownership.

• What changed

  • No file modifications were required: no Snyk config, workflow, or reference exists in the repo.
  • Dependabot remains the only dependency-update configuration under .github/dependabot.yml.

• Resulting state

  • Dependency update automation is consolidated on Dependabot.
  • There is no residual Snyk integration to maintain or remove.

# .github/dependabot.yml
version: 2
updates:
  - package-ecosystem: npm
    directory: "/"

[ioncache]

Since there was no snyk config, this is a no-op